A network may include the interconnection of multiple devices, such as personal electronic entertainment devices. In such a network, interconnected devices may share data, including the sharing of related streams of data. A local service network is an interconnection network on which a variety of user-level services wish to advertise their presence and establish communication without the need for managed network services (such as DHCP—Dynamic Host Configuration Protocol, DNS—Domain Name Service, Jini-Sun Microsystems networking technology) or explicit foreknowledge, such as services that do not have well-known addresses. In such operations, networks commonly use service discovery protocols so that devices can detect the presence of other devices and establish communication. For example, UPNP (Universal Plug and Play) can be used by a personal computer on an unmanaged home network to discover printers that are available on the network, thereby enabling an application to establish communication with such a device and print a document.
There are many discovery protocols in widespread use today. However, these protocols generally require the active participation of any device that wishes to be discovered. Reducing power consumption in electronic devices is a growing requirement, and idle devices typically enter reduced-power states (which may also be referred to as low-power modes, sleep states, slumber modes, standby modes, or other similar terminology) to conserve energy. When a device is in low-power mode, as much functionality and circuitry is disabled as possible. Network devices thus cease communication, thereby rendering them invisible to discovery protocols.
A means may be implemented to remotely awaken a device from reduced-power mode. Modern network devices typically provide such a feature, which may include Wake-on-LAN (WoL), which includes the transmission of a data packet, referred to as a “Magic Packet™”, to awaken devices that have transitioned to a low power state. (See “Magic Packet Technology,”, AMD, Publication 20213, November 1995) A process for waking devices on a network may commonly operate as follows: When a device enters low power mode, the device enables a simple state machine processor that passively monitors network traffic. When a wake signal or packet (such as a Magic Packet for WoL traffic) is observed, the state machine resumes power to the rest of the device and brings up the network for full communication. The wake signal may be formatted as a standard broadcast Ethernet frame that identifies the device to be awakened by its MAC (Media Access Control) address. This process provides a process to awaken an individual device via an explicit request.
However, the conventional technology is useful only when the address of the device to be awakened is known in advance such that the frame may be addressed to such device. In a service network, the addresses of services are generally unknown and may be continually changing, thus providing an anonymous group of devices that need to be awakened in the network.